Apparatus for receiving upon an elevationally displaceable table a stack of flat material



May 20, 1969 F. BAYS 3,4 06

APPARATUS FOR RECEIVING UPON AN EIJEVATIONALLY DISPLACE TABLE A STACK OFFLAT MATERIAL Fig- ,2 Sheet or s INVENTOR I Few/find 194 BY UnitedStates Patent US. Cl. 271-61 7 Claims ABSTRACT OF THE DISCLOSURE Anapparatus for receiving a stack of substantially fiat material which isof the type comprising an elevationally displaceable table means whichincludes a table plate and a support member for said table plate. Thetable plate is advantageously displaceable within limits in asubstantially horizontal plane with respect to the support member uponan air cushion which can be produced between the table plate and suchsupport member.

Background of the invention The present invention relates to an improvedapparatus for receiving a stack of substantially flat material upon anele'vationally displaceable table, in other words a table which can beraised and lowered.

In such type apparatuses it is oftentimes difiicult to deposit the stackin the desired position upon the table by means of a stacker truck forinstance, so that thereafter one sheet of the stack after the other canbe removed by means of a number of lifting devices arranged above thetable for instance. Since a stack of sheet metal for example is veryheavy, and further, inasmuch as the stack must be deposited in an exactrelative position upon the table so that the further conveying ortransport of the individual sheets for processing can take place along apredetermined transport path in a trouble-free manner, it has been foundthat the correct deposition of the stack upon the table entails a timeconsuming maneuver. Furthermore, it must be observed that the so-calledseparating magnets or compressed air nozzles for lifting the uppermostelement of the stack are disposed in the correct spacing with regard tothe stack, since these components are responsible for separating theuppermost sheet somewhat from the remainder of the stack.

Summary of the invention Accordingly, it is a primary object of thepresent invention to provide an improved apparatus of the aforementionedtype which overcomes the drawbacks which existed in the prior artstructures.

Another, more specific object of this invention relates to the provisionof an improved table means for receiving a stack of substantially flatmaterial and which allows for fine positioning of the stack into adesired position in a relatively simple, eflicient and quick manner,with a minimum of effort.

Still a further significant object of the present invention relates tothe provision of an improved elevationally displaceable table meanswhich is of relatively simple construction, economical to manufacture,highly reliable in operation, easy to use, and above all allows forprecise location of the material supported upon such table means indesired position through quick, uncomplicated, relatively effortlessshifting of a fioatingly arranged table plate of the table means whichdirectly carries the stack of material which is to be spatially orientedin desired position.

3,445,106 Patented May 20, 1969 Now, in order to implement these andstill further objects of the invention which will become more readilyapparent as the description proceeds, the inventive apparatus forreceiving a stack of substantially flat material is generallycharacterized by the provision of a table plate which is displaceablewithin limits in a substantially horizontal plane with respect to asupport member upon an air cushion which can be produced between suchtable plate and the aforesaid support member.

Owing to this air cushion it is possible to easily displace, into theproper position, the table plate together with the stack of materiallocated thereon. Consequently,

initially there is only required an approximate depositing of the stackof material being handled upon the table means, for instance by means ofa conventional stacker truck, and thereafter, following this coarsepositioning of the stack it is possible to manually undertake the finepositioning of the stack by virtue of the available air cushion.

Brief description of the drawings The invention will be betterunderstood, and objects other than those set forth above, will becomeapparent, when consideration is given to the following detaileddescription thereof. Such description makes reference to the annexeddrawings wherein:

FIGURE 1 is a vertical sectional view through a preferred embodiment ofthe inventive table means which is located in a position ready toreceive a stack of material which is to be processed;

FIGURE 2 is a top plan view of the table means depicted in FIGURE 1;

FIGURE 3 is a vertical cross-sectional view of the table means depictedin FIGURE 1, however shown in its working position ready for the removalof the sheets of the stack located thereon;

FIGURE 4 is a top plan view of the table means shown in FIGURE 3;

FIGURE 5 is an enlarged fragmentary view showing a. detail of thelocation A designated in FIGURE 1; and

FIGURE 6 is a fragmentary, top plan view of the detail showing depictedin FIGURE 5.

Description of the preferred embodiment Describing now the drawings, theexemplary embodiment of inventive table means T incorporates a frameunit 1, a base plate 2 secured to this frame unit 1, a support member inthe form of an apertured plate member 3 affixed to the base plate 2, andfurther, a so-called table plate 4; This table means T can beadvantageously vertically displaced through the action of a suitablepiston rod 5 or equivalent hoist structure. Columns and guides, whichhave been conveniently omitted from the drawings for purposes ofsimplification, serve to appropriately guide the table means T. Theaforementioned components 1, 2 and 3 are satisfactorily secured to oneanother at their mutual contact or bearing surfaces, as shown, andhence, do not move relative to one another and thus can be verticallyraised and lowered as a composite unit.

It will be additionally observed that a connection nipple or stud 6which communicates with a schematically illustrated supply 20 ofpressurized fluid medium, such as compressed air, is mounted at the baseplate 2. The aforementioned support member in the form of the aperturedplate member 3 is laterally secured in air tight fashion to the baseplate 2 by means of appropriate sealing strips 7 or the like and thesetwo plate members 2, 3 together with the sealing strips 7 enclose asubstantially fiat intermediate air compartment -8, as best observed byreferring to FIGURE 1. Furthermore, this substantially horizontallyarranged apertured plate member 3 is traversed by a plurality or seriesof open-ended bores 11, so that an air communication path exists betweenthe aforesaid intermediate air compartment or chamber 8 and the air gapor space 12 formed in the region between the apertured plate 3 and thetable plate 4 located thereover.

Further, it should be appreciated that the table plate 4 bearing uponthe apertured support member 3 is optionally displaceable in horizontaldirection. Now, if compressed air or the like is introduced between thisapertured plate or support member 3 and the table plate 4, thepreviously considered air gap or space 12 appears above said aperturedplate 3. Additionally, the table plate 4 exhibits a downwardly directedmarginal portion or skirt 13 at its four sides, so that such table plate4 can be horizontally displaced, as indicated in the drawings, withrespect to the apertured support or plate member 3 until contact withsuch marginal portion 13.

By referring to FIGURE 2 it will be noticed that elastic members, forinstance in the form of compression springs 16 or the like are supportedat one respective end at both sides 14 and 15 of the apertured platemember 3. The other or opposite end of each of these spring members 16is supported at the downward skirt or marginal portion 13 of the tableplate 4. These spring members 16 strive to maintain the table plate 4 inthe position shown in FIGURE 2 with respect to the other components 1,2, and 3 of the table means T. Further. the support or bearing locationsof these spring members 16 at the marginal portion 13 or at theapertured support member 3 can be displaced in horizontal direction.Additionally, the described apparatus is further externally providedwith a plurality of substantially vertically disposed impact members 17against which bears a stack 18 of the material to be processed and whichhas been placed upon the table plate 4. This stack 18 of material,typically in flat form, bears upon a pallet 19 and is placed upon thetable plate 4 by means of a suitable, non-illustrated stacker truck forinstance. This stack '18 can consist of sheet metal, paper, cardboard,plastic, foils or similar flat material.

The heretofore described apparatus functions as follows: If the lastfoil or the like of a stack 18, which has previously been deposited uponthe table means T, has been automatically withdrawn or removed from thepallet 19, then the entire table means T is moved downwardly by means ofthe lifting mechanism, in this case for instance the piston rod 5 orequivalent structure. Now, upon introducing compressed air or the likethrough the connection nipple or pipe 6 into the compartment 8 suchcompressed air will flow through the open-ended bores 11 of theapertured plate member 3 and beneath the area of the table plate '4.This compressed air provides an air cushion in the air gap 12 betweenthe table plate 4 and the apertured plate member 3, so that the tableplate 4 can be easily raised and is maintained in so-called floatingcondition with respect to the apertured plate member 3. It shouldfurther be appreciated that the compressed air then flows between thetable plate 4 and the apertured plate member 3 towards the marginalportion or skirt 13 of the aforesaid table plate 4, and from thislocation such air flows into the surrounding atmosphere.

In this floating position of the table plate 4 the force of the springmembers 16 is suflicient to press the empty table plate 4 into theposition shown in FIGURES l and 2.. This is the starting position of thetable means T for placement of a new stack onto the table plate 4. Sucha stack 18 of material is deposited onto the table plate 4 by means of asuitable stacker truck for instance. In this respect, the stack 18should be located approximately in the middle of the table plate 4 andshould have about the same spacing from the marginal portion or skirt 13or, depending upon the size of the individual sheets of the stack 18.such should extend approximately at the same spacing past the marginalportion 13 of this table plate 4.

Now, in order to carry out the so-called fine adjustment of the stack 18compressed air or the like is thereafter introduced via the connectingpipe 6 from the supply source 20 into the compartment 8. Consequently,the table plate 4 together with the stack 18 located thereon is againheld in the so-called floating or suspended condition owing to the aircushion which has formed in the gap or space 12. Furthermore, the stack18 together with the table plate 4 can be now easily manually brought tobear against the impact members 17. When this exact position of thestack 18 has been maintained, then the introduction of the compressedair through the connection pipe 6 is again shut off so that the tableplate 4 settles upon the apertured plate member 3. The individual sheets18a or the like of the stack 18 can now be individually raised by meansof appropriate lifting elments or the like as is known to the art, forinstance suction cups. The reduction in the height of the stack 18 iscompensated by upward displacement of the table means T by means of thepiston rod 5 or equivalent structure. During such removal of theindividual sheets 18a of the stack 18 the table means is located in theposition shown in FIGURES 3 and 4 and the elastic spring members 16 arepre-stressed. These spring members 16 are advantageously constructed anddimensioned in such a manner that they cannot displace the table plate 4from the position of FIGURES 3 and 4 into the position of FIGURES 1 and2 when no air cushion has been built up between the table plate 4 andthe apertured plate or support member 3. As soon as the last sheet 18aor the like of the stack 18 has been removed from the pallet 19, then,compressed air is introduced once again via the connection pipe 6 and anair cushion forms between the table plate 4 and the apertured support orplate member 3. As a result, this table plate '4 is now once againdisplaced by the pre-stressed spring members 16 into the startingposition of FIGURE 2. The table plate 4 is therefore again in readinessfor receiving a new stack 18, and the entire procedure is repeated inthe manner previously considered.

As should be apparent, the objects initially set forth at the outset ofthis specification have been successfully achieved. Accordingly, what isclaimed is:

1. An apparatus for receiving a stack of substantially flat material,said apparatus comprising a table means, means for elevationallydisplacing said table means, said table means including a table plateand a support member for said table plate, means for displacing saidtable plate within limits in a substantially horizontal plane withrespect to said support member, and means for producing an air cushionbetween said table plate and said support member, said table plate beingdisplaceable in said substantially horizontal plane upon said aircushion.

2. An apparatus for receiving a stack of substantially flat materials asdefined in claim 1, wherein said support member is defined by anapertured plate member disposed beneath said table plate, a base platelocated in spaced relation beneath said apertured plate member to definetherebetween a fluid compartment, means for sealing said fluidcompartment at all sides, a source of pressurized fluid mediumcommunicating with said fluid compartment.

3. 'An apparatus for receiving a stack of substantially flat material asdefined in claim 2, wherein said fluid compartment is adapted to receivecompressed air, said source of pressurized fluid medium furnishingcompressed air to said fluid compartment.

4. An apparatus for receiving a stack of substantially flat material asdefined in claim 3, wherein said table means further includes framemeans for supporting said base plate.

5. An apparatus for receiving a stack of substantially flat material asdefined in claim 3, wherein said apertured plate member includes aseries of open-ended bores communicating said fluid compartment with theregion between said table plate and said apertured plate member so thatpressurized air moves into said region to floatingly suspend said tableplate with respect to said apertured plate member.

6. An apparatus for receiving a stack of substantially flat material asdefined in claim 1, further including elastic means for urging saiddisplaceable table plate in said substantially horizontal plane towardsa predetermined terminal position thereof.

7. An apparatus for receiving a stack of substantially flat material asdefined in claim 1, said apparatus further including a plurality offixed, substantially vertically disposed impact member means for contactby a stack of flat material when disposed upon said table means and forguiding the same.

References Cited UNITED STATES PATENTS 3,022,997 2/ 1962 Pendley 27 l613,025,052 3/ 1962 Gutteling 271--28 3,260,402 7/1966 Lareau 27161RICHA'RD E. AEGERTER, Primary Examiner.

